Monitoring device for monitoring the state of the circulation of a patient and computer program product for this monitoring

ABSTRACT

A monitoring device for the circulation of a patient includes sensors for recording data, an input unit for inputting patient specific data and a connected a data recording and analysis device configured to determine the right atrial pressure (RAP), the mean arterial pressure (MAP) and the cardiac output (CO) and to determine the mean systemic filling pressure (Pms) and to determine the cardiac efficiency (Eh) therefrom. A device records a pressure value (Pps,char) characterizing the pressure assistance during positive-pressure ventilation. The data recording and analysis device is configured to determine a pressure-corrected mean systemic filling pressure (Pms p ) and a pressure-corrected cardiac efficiency (Eh p ) by the difference from the right atrial pressure (RAP) and the pressure value (Pps,char) characteristic of the pressure assistance being used instead of the right atrial pressure (RAP). A display device displays the pressure-corrected mean systemic filling pressure (Pms p ) and the pressure-corrected cardiac efficiency (Eh p ).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a United States National Phase Application ofInternational Application PCT/EP2014/002902 filed Oct. 29, 2014 andclaims the benefit of priority under 35 U.S.C. §119 of German PatentApplication 10 2013 018 366.9 filed Nov. 2, 2013 the entire contents ofwhich are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention pertains to a monitoring device for monitoring thestate of the circulation of a patient with sensors for recording datacharacterizing the current state of circulation of the patient, an inputunit for inputting the person-specific data of the patient, a datarecording and analysis device connected to the sensors and the inputunit, which is set up to determine the right atrial pressure (RAP), themean arterial pressure (MAP) and the cardiac output (CO) from the datacharacterizing the current state of circulation of the patient and todetermine the mean systemic filling pressure (Pms) from the right atrialpressure, mean arterial pressure and cardiac output and to determine thecardiac efficiency (Eh) from the mean systemic filling pressure and fromthe right atrial pressure (RAP) by means of linear combination withpredetermined factors and with factors dependent on the person-specificdata and to display the currently determined mean systemic fillingpressure (Pms) and the current cardiac efficiency (Eh) as a currentstate in a system of coordinates defined by the cardiac efficiency andthe mean systemic filling pressure on a display device.

BACKGROUND OF THE INVENTION

Such a monitoring device for monitoring and displaying the state of thecirculation of a patient is well known from WO 2009/094700 A1. Themonitoring of the circulatory function of patients is a central task inintensive care. The monitoring involves the recording of variousrelevant parameters with sensors in order to derive variables therefromsuch as various blood pressure values, blood volume pulses, cardiacoutput, heart rate, oxygen concentrations, etc. Physicians or medicalstaff then have to get an idea from these variables of whether the stateof the circulation is within a physiologically normal range or whetherthe circulation is in a critical state with possible malfunctions suchthat countermeasures shall be taken. A countermeasure may be theadministration of additional volumes, e.g., infusion of saline solution,or the administration of various drugs, e.g., of vasoconstricting orvasodilating drugs, or of drugs which have an effect on the activity ofthe heart. The physician or the medical staff must decide which of themeasures are to be taken and in which direction on the basis of a largernumber of variables related to the state of the circulation because ofpredefined strategies and empirical values.

These variables related to state of the circulation can only beinterpreted with difficulty in their entirety and in their interactionsuch that the decision on taking therapeutic countermeasures and thetype of therapeutic countermeasures is a complicated problem for themedical staff. For this reason, approaches have already been provided toderive variables from the measured variables of the circulatory functionand to display them on a display device, which makes the state of thecirculation intuitively more easily recordable. Among other things, itis suggested in the above-mentioned publication WO 2009/094700 todetermine the mean systemic filling pressure Pms and the cardiacefficiency Eh as derived variables and display them in a system ofcoordinates with the mean systemic filling pressure and the cardiacefficiency as axes of coordinates. The system of coordinates does nothave to be a Cartesian system in this case, but rather may also beimplemented by two parallel, adjacent or otherwise shown axes ofcoordinates, at which the current values of both variables are shown.

In the cited publication, the mean systemic filling pressure Pms isderived by the following equation:

Pms=a·RAP+MAP+c·CO   [1]

in which a and b are predetermined factors and c is a factor, whichdepends on person-specific data (e.g., age, height, gender) in apredetermined manner.

In this case, the variable RAP is the right atrial pressure, MAP is thearterial mean pressure and CO is the cardiac output, a and b arepredetermined, person-independent factors, and factor c is determined bya predetermined dependence from person-specific data (e.g., age,height).

The cardiac efficiency is derived by the following equation:

$\begin{matrix}{{Eh} = {\frac{{Pms} - {R\; A\; P}}{Pms} = \frac{{{a \cdot R}\; A\; P} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O} - {R\; A\; P}}{{{a \cdot R}\; A\; P} + {{b\; \cdot M}\; A\; P} + {{c \cdot C}\; O}}}} & \lbrack 2\rbrack\end{matrix}$

If the heart is working too weakly, the RAP value increases, which leadsto a decrease in the cardiac efficiency Eh. If the heart stops beating,all pressures are essentially equal to the mean systemic fillingpressure Pms such that the cardiac efficiency Eh drops essentially to 0.Further connections and background are described in the article“Therapeutic Control of the Circulation” by W. G. Parkin et al., Journalof Clinical Monitoring and Computing 2008, 22:391-400.

It is also possible in this connection to display the state values ofthe pair of values Pms and Eh at consecutive points in time, e.g., as asequence of points in a system of coordinates so that the course ofdevelopment of the state of the circulation is visible.

An artificial ventilation with positive-pressure ventilation must oftenalso be carried out in patients in intensive care units. It has beenfound that the monitoring of the state of the circulation described inthe introduction with determination of the mean systemic fillingpressure and the cardiac efficiency and the display thereof does notlead to satisfactory and reproducible results in patients withpositive-pressure ventilation.

SUMMARY OF THE INVENTION

An object of the present invention is to create a monitoring device formonitoring the state of the circulation, with which consistent andreproducible results for the considered state variables of thecirculation can also be achieved in positive-pressure-ventilatedpatients. Further, a computer program product shall be indicated whichmakes possible a consistent and reproducible determination of the statevariables, mean systemic filling pressure Pms and cardiac efficiency Eh,on a computer basis during the process on a data recording and analysisdevice.

A device for recording a pressure value, which characterizes thepressure assistance during the positive-pressure ventilation, is presentin the monitoring device according to the present invention. Thispressure value characterizing the pressure assistance duringpositive-pressure ventilation is abbreviated below as Pps,char. Thischaracteristic pressure value shall be an indicator of the mean pressureassistance and may be a measured pressure value or a pressure valuereceived by a ventilator, set thereon or derived therefrom. The datarecording and analysis device is configured to record the characteristicpressure value and to determine a pressure-corrected mean systemicfilling pressure (Pms_(p)) and a pressure-corrected cardiac efficiency(Eh_(p)) by using the difference from the right atrial pressure (RAP)and the pressure value characteristic of the pressure assistancePps,char instead of the right atrial pressure (RAP) in the equations forthe determination thereof. This pressure-corrected mean systemic fillingpressure Pms_(p) and the pressure-corrected cardiac efficiency Eh_(p)are displayed by the data recording and analysis device as a currentstate in the system of coordinates on the display device.

It has been found that a more accurate determination of the actual statevariables in the circulatory system is possible by including thepressure conditions in the respiratory system. For this purpose, thepressure value characterizing the pressure assistance shall besubtracted from the recorded right atrial pressure RAP, since therecorded right atrial pressure RAP in the circulatory system wouldotherwise be assumed to be too high. It has been shown that the simplesubtraction of the right atrial pressure RAP that was recorded bysensors minus the pressure characterizing the pressure assistance leadsto a pressure-corrected right atrial pressure, which corresponds muchbetter to the actual right atrial pressure without positive-pressureventilation.

In a preferred embodiment, provisions are made for the data recordingand analysis device to be set up to determine the pressure-correctedmean systemic filling pressure (Pms_(p)) on the basis of the followingequation:

Pms _(p) =a·(RAP−0.76·Pps,char)+b·MAP=c·CO   [3]

-   -   in which:    -   RAP is the right atrial pressure (mmHg)    -   MAP is the mean arterial pressure (mmHg)    -   CO is the cardiac output (L/min)    -   Pps,char is the pressure characterizing the pressure assistance        (mbar)    -   a is the predetermined factor (dimensionless)    -   b is the predetermined factor (dimensionless)    -   c is the person-specific factor (dyn·sec·cm⁻⁵·m²).

In the given equation, the characteristic pressure Pps,char issubtracted with a factor of 0.76 since the pressure values in thecirculatory system traditionally are given in the unit mmHg, but thepressure in the respiratory system as Pps,char is given in mbar. Due tothe factor of 0.76, the different units are balanced such that thesimple difference from RAP and Pps,char is actually obtained if bothpressures RAP and Pps,char would be obtained in the same unit. It hasbeen shown that the complete subtraction of the pressure Pps,char fromthe right atrial pressure RAP leads to the best results.

In an advantageous embodiment, provisions are made for the datarecording and analysis unit to be set up to determine thepressure-corrected cardiac efficiency (Eh_(p)) according to thefollowing equation:

$\begin{matrix}{{Eh}_{p} = \frac{\begin{matrix}{\left\lbrack {{a \cdot \left( {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right)} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O}} \right\rbrack -} \\\left\lbrack {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right\rbrack\end{matrix}}{{a \cdot \left( {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right)} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O}}} & \lbrack 4\rbrack\end{matrix}$

with the meanings of the variables given in the previous formula.

The just indicated formula corresponds to the formula already givenabove

${Eh} = \frac{{Pms} - {R\; A\; P}}{Pms}$

in which the right atrial pressure RAP is continuously replaced (even atthe point, at which it occurs in Pms) with a pressure-corrected value(RAP−0.76″ Pps,char).

In the preferred embodiment, the device for recording the pressure valuecharacterizing the pressure assistance is configured to record thepositive end-expiratory pressure PEEP as this characterizing pressurevalue Pps,char. The data recording and analysis device is then set up touse the difference from the right atrial pressure RAP and the positiveend-expiratory pressure PEEP in each case rather than the right atrialpressure RAP determined by sensors in the determination of thepressure-corrected mean systemic filling pressure (Pms_(p)) and in thedetermination of the pressure-corrected cardiac efficiency (Eh_(p)), andespecially to insert the variable PEEP for Pps,char in theabove-mentioned equations for Pms_(p) and Eh_(p). The positiveend-expiratory pressure (PEEP) is a pressure value advantageouslycharacterizing the pressure assistance since it reflects the meanincrease in the pressure level due to the positive-pressure ventilationand thus is a good indicator of the pressure value in order to reducethe recorded right atrial pressure RAP in the circulatory system inorder to have a corrected right atrial pressure enter into thedeterminations of Pms_(p) and Eh_(p), which rather reflects the actualstate of circulation without positive-pressure ventilation.

According to an advantageous embodiment, provisions are made for thedata recording and analysis device to be set up to store the states ofpressure-corrected mean systemic filling pressure (Pms_(p)) andpressure-corrected cardiac efficiency (Eh_(p)) as a function of time andto display the current state from the current pressure-corrected meansystemic filling pressure (Pms_(p)) and pressure-corrected cardiacefficiency (Eh_(p)) together with the stored states at past points intime in the system of coordinates in order to make the course ofdevelopment of the state visible. In this way, it is possible for thestaff to monitor in an intuitively easily recordable manner whethercountermeasures possibly taken have led to an improvement in the stateof the circulatory system. In particular, provisions may advantageouslybe made in this case for the data recording and analysis device to beset up to display the course of development as a state curve ortrajectory (Pms_(p)(t), Eh_(p)(t)) with a time stamp in the system ofcoordinates. The time stamp may occur, for example, along the trajectoryby indicating times along the curve.

According to another aspect, the present invention is directed at acomputer program product which is configured to control the datarecording and analysis device on a computer basis when said computerprogram product is being run on the device such that the device performsthe above-described procedures of the monitoring device as modes ofoperation of the data recording and analysis device.

The present invention is explained below on the basis of exemplaryembodiments in connection with the drawings. The various features ofnovelty which characterize the invention are pointed out withparticularity in the claims annexed to and forming a part of thisdisclosure. For a better understanding of the invention, its operatingadvantages and specific objects attained by its uses, reference is madeto the accompanying drawings and descriptive matter in which preferredembodiments of the invention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1 is a schematic view of the display of a display device of amonitoring device according to the present invention for the statedisplay for a patient; and

FIG. 2 is a schematic view showing a second example of a state displayfor another patient.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A male patient with the following data is considered as the firstexample:

-   -   Patient: Male, 55 years old, 178 cm, 76 kg (normal weight),        acute lung failure after hemorrhage;    -   cardiac index 5.0 L/min./m2, heart rate 97 per min., blood        pressure 128/61 mmHg (MAP 81 mmHg), RAP 15 mmHg;    -   controlled ventilation with a positive end-expiratory pressure        PEEP of 15 mbar.

Thus, the following values were obtained for the state variables byderiving the mean systemic filling pressure Pms and the cardiacefficiency Eh without pressure correction, i.e., by using the formulas[1] and [2]:

-   Pms=26.01 (clinical evaluation: too high)-   Eh=0.35 (clinical evaluation: low).

The pressure-corrected mean systemic filling pressure Pms_(p) wassubsequently determined with the formula [3] and the pressure-correctedcardiac efficiency Eh_(p) was determined with the equation [4], whichleads to the following values for the pressure-corrected statevariables:

-   Pms_(p)=15.07 (clinical evaluation: too low)-   Eh_(p)=0.63 (clinical evaluation: good).

FIG. 1 shows a schematic view of the display of a display device, inwhich the state variables are shown without pressure correction (roundmark) and the pressure-corrected state variables (square mark) as pointsin a Cartesian system of coordinates comprising the cardiac efficiencyEh and the mean systemic filling pressure Pms. This example shows that amarkedly different evaluation results from the previous derivation anddisplay (without pressure correction). After deriving thepressure-corrected state variables, the result is obtained that the meansystemic filling pressure is actually too low and the cardiac efficiencyis actually good, which produces the exact opposite of the evaluation ofthe state variables without pressure correction and which requires othercountermeasures. The evaluation with the pressure-corrected statevariables Pms and Eh is actually very much closer to reality and alsocorresponded to the evaluation of the clinician and is consistent withother measured hemodynamic parameters (good heartbeat performance,normal blood pressure, high performance of ejection, low RAP under PEEP)such that a markedly improved recording of the state of circulation dueto the corrected state variables Pms_(p) and Eh_(p) is assumed.

In another example, the circulation of a patient with the following datawas monitored:

-   -   Patient: Male, 72 years old, 180 cm, 103 kg (overweight), acute        lung failure after massive transfusion;    -   cardiac index 4.2 L/min./m2, heart rate 86 per min., blood        pressure 131/51 mmHg (MAP 71 mmHg), RAP 14 mmHg;    -   assisted spontaneous breathing with a PEEP of 12 mbar.

Without taking the pressure assistance into consideration, the followingvalues are obtained for the mean systemic filling pressure Pms and thecardiac efficiency Eh from the right atrial pressure RAP, the meanarterial pressure MAP and the cardiac output CO:

-   Pms=21.81 (clinical evaluation: adequate)-   Eh=0.39 (clinical evaluation: low).

By carrying out the pressure correction, the followingpressure-corrected state variables are obtained again in this examplewith the formulas [3] and [4]:

-   Pms_(p)=13.05 (clinical evaluation: too low)-   Eh_(p)=0.63 (clinical evaluation: good).

The graphic representation of these state variables is shown in FIG. 2in a Cartesian system of coordinates with the cardiac efficiency on theY axis and the mean systemic filling pressure on the X axis, and thederived values of the state variables after conventional determinationare shown with a round symbol and the state variables determinedaccording to the present invention with pressure correction are shownwith a square symbol. It is also shown here that after taking intoconsideration the pressure correction, a markedly different evaluationof the state of the circulation of the patient is made: Without pressurecorrection, the mean systemic filling pressure Pms would be evaluated asadequate and the cardiac efficiency Eh as too low, whereas after takingthe pressure correction into consideration, a markedly differentevaluation of the state of the circulation of the patient is obtained,namely a pressure-corrected mean systemic filling pressure, which isevaluated as too low, and a pressure-corrected cardiac efficiencyEh_(p), which is evaluated as good. This evaluation after pressurecorrection also corresponded to the evaluation of the clinician and isconsistent with the other measured hemodynamic parameters (goodheartbeat performance, normal blood pressure, high ejection performance,low RAP under PEEP).

It is consequently shown that a markedly more reliable recording of thestate of the circulatory system of positive-pressure-ventilated patientsis achieved with the monitoring device according to the presentinvention compared to the state of the art.

While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

1. A monitoring device for monitoring the state of the circulation of apatient: sensors configured to record data characterizing the currentstate of circulation of the patient; an input unit for inputtingperson-specific data of the patient; a data recording and analysisdevice connected to the sensors and connected to the input unit andconfigured to determine the right atrial pressure, the mean arterialpressure and the cardiac output from the data characterizing the currentstate of circulation of the patient and to determine the mean systemicfilling pressure from the right atrial pressure, the mean arterialpressure and the cardiac output and to determine the cardiac efficiencyfrom the mean systemic filling pressure and from the right atrialpressure by means of linear combination with predetermined factors andwith factors dependent on the person-specific data and to display thecurrently determined mean systemic filling pressure and the currentcardiac efficiency as a current state in a system of coordinates definedby the cardiac efficiency and the mean systemic filling pressure on adisplay device; a pressure value recording device configured to record apressure value characterizing the pressure assistance duringpositive-pressure ventilation, wherein: the data recording and analysisdevice is further configured to determine a pressure-corrected meansystemic filling pressure and a pressure-corrected cardiac efficiency asa function of a difference from the right atrial pressure and thepressure value characteristic of the pressure assistance being used; anda display device displaying the pressure-corrected mean systemic fillingpressure and the pressure-corrected cardiac efficiency as a currentstate in a system of coordinates on the display device.
 2. A monitoringdevice in accordance with claim 1, wherein the data recording andanalysis device is configured to determine the pressure-corrected meansystemic pressure (Pms_(p)) on the basis of the following equation:Pms _(p) =a·(RAP−0.76·Pps,char)+b·MAP=c·CO in which: RAP: is the rightatrial pressure (mmHg) MAP: is the mean arterial pressure (mmHg) CO: isthe cardiac output (L/min) Pps, char: is the pressure characterizing thepressure assistance (mbar) a: is a predetermined factor (dimensionless)b: is a predetermined factor (dimensionless) c: is a person-specificfactor (dyn·sec·cm⁻⁵·m²).
 3. A monitoring device in accordance withclaim 2, wherein the data recording and analysis device is configured todetermine the pressure-corrected cardiac efficiency (Eh_(p)) accordingto the following equation: ${Eh}_{p} = {\frac{\begin{matrix}{\left\lbrack {{a \cdot \left( {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right)} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O}} \right\rbrack -} \\\left\lbrack {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right\rbrack\end{matrix}}{{a \cdot \left( {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right)} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O}}.}$4. A monitoring device in accordance with claim 1, wherein the pressurevalue recording device for recording the pressure value characterizingthe pressure assistance Pps,char is configured to record the positiveend-expiratory pressure, and the data recording and analysis device isfurther configured to use a difference from the right atrial pressureand the positive end-expiratory pressure in determining thepressure-corrected mean systemic filling pressure and in determining thepressure-corrected cardiac efficiency.
 5. A monitoring device inaccordance with claim 1, wherein the data recording and analysis deviceis further configured to store the states of the pressure-corrected meansystemic filling pressure and pressure-corrected cardiac efficiency as afunction of time and to display the current state from the currentpressure-corrected mean systemic filling pressure and thepressure-corrected cardiac efficiency together with the stored states atpast points in time in the system of coordinates, whereby a course ofdevelopment of the state is visible.
 6. A monitoring device inaccordance with claim 5, wherein the data recording and analysis deviceis further configured to display the course of development as a statecurve or trajectory with a time stamp in the system of coordinates.
 7. Acomputer program product for monitoring the state of the circulation ofa patient, wherein the computer program product is configured to controlthe operation of a data recording and analysis device on a computerbasis when said computer program product is being run on said datarecording and analysis device such that the data recording and analysisdevice: receives and stores data characterizing the current state ofcirculation of the patient from sensors; receives and storesperson-specific data of the patient from an input unit; determines theright atrial pressure, the mean arterial pressure and the cardiac outputfrom the data characterizing the current state of circulation of thepatient and determines the mean systemic filling pressure from the rightatrial pressure, mean arterial pressure and cardiac output anddetermines the cardiac efficiency from mean systemic filling pressureand from the right atrial pressure by means of linear combination withpredetermined factors and with factors dependent on the person-specificdata and displays the currently determined mean systemic fillingpressure and the current cardiac efficiency as a current state in asystem of coordinates defined by the cardiac efficiency and the meansystemic filling pressure on a display device, wherein the computerprogram product is further configured to control the operation of thedata recording and analysis device when said computer program product isbeing run on said data recording and analysis device, whereby: the datarecording and analysis device receives and stores a pressure valuecharacterizing the pressure assistance during positive-pressureventilation from a device for recording this pressure value; and apressure-corrected mean systemic filling pressure and apressure-corrected cardiac efficiency are determined as a function of adifference from the right atrial pressure and the pressure valuecharacteristic of the pressure assistance being used and displays thepressure-corrected mean systemic filling pressure and thepressure-corrected cardiac efficiency as a current state in the systemof coordinates on the display device.
 8. A computer program product inaccordance with claim 7, wherein the computer program product isconfigured to control the data recording and analysis device when saidcomputer program product is being run on said data recording andanalysis device in order to receive a positive end-expiratory pressureas a pressure value characterizing the pressure assistance and in orderto determine the pressure-corrected mean systemic filling pressure onthe basis of the following equation:Pms _(p) =a·(RAP−0.76·Pps,char)+b·MAP=c·CO in which: RAP: is the rightatrial pressure (mmHg) MAP: is the mean arterial pressure (mmHg) CO: isthe cardiac output (L/min) Pps,char: is the pressure characterizing thepressure assistance (mbar) a: is a predetermined factor (dimensionless)b: is a predetermined factor (dimensionless) c: is a person-specificfactor (dyn·sec·cm⁻⁵·m²).
 9. A computer program product in accordancewith claim 8, wherein the computer program product is configured tocontrol the data recording and analysis device when said computerprogram product is being run on said data recording and analysis devicesuch that the data recording and analysis device determines thepressure-corrected cardiac efficiency according to the followingequation: ${Eh}_{p} = {\frac{\begin{matrix}{\left\lbrack {{a \cdot \left( {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right)} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O}} \right\rbrack -} \\\left\lbrack {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right\rbrack\end{matrix}}{{a \cdot \left( {{{R\; A\; P} - {0.76 \cdot {Pps}}},{char}} \right)} + {{b \cdot M}\; A\; P} + {{c \cdot C}\; O}}.}$10. A computer program product in accordance with claim 7, wherein thecomputer program product is configured to control the data recording andanalysis device when said computer program product is being run on saiddata recording and analysis device such that the data recording andanalysis device determines the pressure-corrected mean systemic fillingpressure and the pressure-corrected using the positive end-expiratorypressure as the pressure value Pps,char characterizing the pressureassistance during positive-pressure ventilation.
 11. A computer programproduct in accordance with claim 7, wherein the computer program productis configured to control the data recording and analysis device whensaid computer program product is being run on said data recording andanalysis device such that the data recording and analysis device storesthe states of pressure-corrected mean systemic filling pressure andpressure-corrected cardiac efficiency as a function of time and displaysthe current state from the current pressure-corrected mean systemicfilling pressure and the pressure-corrected cardiac efficiency togetherwith the stored states at past points in time in the system ofcoordinates in order to make the course of development of the statevisible.
 12. A computer program product in accordance with claim 11,wherein the computer program product is configured to control the datarecording and analysis device when said computer program product isbeing run on said data recording and analysis device such that the datarecording and analysis device displays the course of development as astate curve or trajectory with a time stamp along the curve in thesystem of coordinates.